Find \(\int_{π/4}^{π/2}7 \,cos⁡x \,dx\).

• A. 7(1-\(\frac{1}{\sqrt{2}}\))
• B. -7(1-\(\frac{1}{\sqrt{2}}\))
• C. 7(1+\(\frac{1}{\sqrt{2}}\))
• D. 7(\(\sqrt{2}-\frac{1}{\sqrt{2}}\))